Process and product for image transfer photography



Nov. 14, 1967 D. M. HARVEY Y3,352,674

PROCESS AND PRODUCT FOR IMAGE TRANSFER PHOTOGRAPHY DONALD M. HARVEYINVENTOR.

A T TORNE YS Nov. 14, 1967 D. M. HARVEY 3,352,674

PROCESS AND PRODUCT FOR IMAGE TRANSFER PHOTOGRAPHY Filed Jan. 20, 1964 5ShetS-Sheet 2 DONALD M. *HA/ VEY INVENTOR,

A T TOR/VE YS Nov. 14, 1967 D. M. HARVEY 3,352,674

PROCESS AND PRODUCT FOR IMAGE TRANSFER PHOTOGRAPHY Filed Jan. 20, 1964 5Sheets-Sheet 3 DONALD M HARVEY INVENTOR.

A 7' TUR/VE YS United States Patent O 3,352,674 PRCESS AND IRB'UCI FORIMAGE TRANSFER PHG'QF-RAPHY Donald M. Harvey, Webster, NX., assigner toEastman Kodak Company, Rochester, NX., a corporation of New Jersey FiledJan. Ztl, '1964, Ser. No. 333,773 17 Claims. (Cl. 96-29) ABSTRACT F THEDISCLGSURE An apparatus having superimposed film land receiver sheetssealed around their peripheral edges to form a fluid-tight envelope. Theenvelope may include a pod or fluid container filled with processingfluid and a iiuid trapping section spaced from the fluid container andincluding a highly absorbent pad for receiving excess fluid, thetrapping section and envelope being separated by a rupturable seal. Aprocess wherein developing fluid is injected into the envelope from theattached fluid container or by other means and a positive pressure isexerted on the envelope during a soak and development period to assuredistribution of the fluid throughout the envelope an maintain the fluidand receiver sheets in spaced relation. At the end of this period thesheets are pressed together to bring them into intimate contact forimage transfer. Such action ruptures the seal between the envelope andtrapping section so that excess fluid is absorbed by the pad therein.

This invention relates to an irnproved process and product for use inimage transfer photography.

Image transfer photography is well known in the art .and products andapparatus for use with such photography have been commercially availablefor many years. Where, as is particularly desirable, the processing isto be done within a camera structure, it is essential that theprocessing materials be so confined or of such nature that they will notcontaminate the interior of the camera. Where such process has been usedfor in-camera processing it has been customary, after exposure of thesensitized sheet or strip of film material, to apply a relatively thick,viscous processing fluid to the sheet adjacent the image area and tospread it across the image area in a uniform layer by progressivelysandwiching the sensitized sheet with a sheet of transfer-imagereceiving material. One of the biggest problems with such materials andprocess has been in obtaining the desired uniformity of thickness of theviscous processing fluid. As is well known, any variation in thicknessof such layer results in a variation in density in the finished transferimage. Moreover, when color materials are involved, any variation inthickness of the layer not only affects the density but also therelative color composition. As a result carneras using such a systemhave necessarily required the use of parts of relatively high precision.Moreover, the viscosity of the processing fluid tends to changeappreciably with temperature, thereby affecting its spreading propertiesand tending to make it still more difficult to obtain uniformity oflayer thickness under diiferent temperature conditions. In addition,even with the viscous uid used, it has been practically impossible toavoid some contamination of the processing apparatus used.

It is an object of this invention to provide an improved image-transferfilm product, and a process for using this product, which will overcomethese defects.

A further object is to provide such a product and process adapted to usea relatively free-flowing processing uid so confined in the productduring the processing 3,352,674 Patented Nov. I4, i967 operation as toprevent contamination of the processing apparatus.

These and other objects are obtained by providing a sandwichconstruction wherein the film `and transferimage-receiving sheets or`strips are either secured together around the edges of their imageareas or are adapted to be held sealed together during processing so asto effectively form a fluid-tight envelope. During processingfree-flowing processing liquid is injected into this envelope insufficient quantities `and under such pressure as to positively hold theopposed walls, which carry the image areas, spaced materially apart fromone another throughout a predetermined soak period. At the end of thisperiod the image areas are pressed together into intimate face-to-facerelationship so that all excess liquid is forced from therebetween andare held in this relationship until image transfer has been completed.Preferably the sandwich incorporates a fluid trapping section whichincludes a pad of highly absorbent material isolated from the imageareas during the soaking period and into which the excess fluid isforced when the image areas are pressed together for image transfer.

My improved process and several illustrative embodiments of my improvedphotographic product and apparatus for practicing this process Iareshown in the accompanying drawing wherein:

FIG. 1 is a plan view of an image transfer film sandwich constructionembodying my invention;

FIG. 2 is a longitudinal section through the sandwich of FIG. l;

FIGS. 3, 4, and 5 illustrate successive steps involved in using thesandwich of FIG. 1 in accordance with my improved process;

FIGS. 6 and 7 illustrate a slightly modified method of practicing myimproved process;

FIG. 8 illustrates an alternative form of film product in accordancewith my invention;

FIG. 9 is a longitudinal section through the sandwich of FIG. 8;

FIG. l0 illustrates one stage during the processing of a sandwich of thetype shown in FIG. 8;

FIG. 1l illustrates another form of sandwich construction as well as themanner of processing this form;

FIG. 12 illustrates a slightly modified method of processing a sandwichconstruction of the type shown in FIG. 11;

FIG. 13 shows a form of processing apparatus especially useful inpracticing the improved process in accordance with my invention; and

FIG. 14 is a -somewhat diagrammatic sectional view through a cameraadapted for use with the materials and processing method in accordancewith my invention.

An image transfer product in accordance with my invention is shown inFIG. 1 and 4comprises a sandwich 1 formed by superimposed sheets 2, 3which are sealed together around their periphery as cliagrammaticallyindicated by the X--hatched areas 4, 5, 6, and 7, in FIG. 1, wherebythey form a fluid-tight envelope. Extending transversely across thesandwich near one end is an additional seal indicated at S adapted toisolate the image portion 9 of the sandwich from a trapping portion 1t)located at one end thereof. Seal 8 is made considerably weaker thanseals d to 7, so that it will rupture when a predetermined uid pressurehas .been built up within the image portion of the envelope. Seal 8 maybe formed in a manner similar to the rupturable seal on the pods ofviscous processing fluid such as are commonly employed in commerciallyavailable image transfer products and which are described, for example,in U.S. Patent 2,543,181. At least those portions of the inner faces ofsheets 2 and 3 which are outlined by the dash-dot line 11 in FIG. 1constitute the useful image areas of the sheets, one of which isphotosensitive and the other of which is adapted to receive an image lbytransfer when processed in conjunction with the photosensitive area inthe presence of an appropriate processing fluid. While either sheetcould carry the .photosensitive image area, I have shown sheet 2 ascarrying the photosensitive image area designated 12, and sheet 3 ascarrying the transfer-image-receptive area 13..In order to permitexposure of the photosensitive area at least one of the sheets must alsobe transparent to actinic rays. Again, for illustrative purposes, it isassumed that photosensitive sheet 2 is transparent and receiving sheet 3is opaque.

Preferably the fluid-trapping portion of the sandwich includes a pad 14of highly absorbent material, such as blotting paper, cloth7 gauze, orthe like, which, as briefly explained above, will tend to rapidly absorband hold the excess processing fluid.

It is intended that in processing the sandwich of FIG. l, suitablefree-flowing processing liquid 15 will .be injected between the imageareas 12 and 13 of sheets 2 and 3.

This may be accomplished with the aid of a suitable syringe 16, the tip17 of which is adapted to pierce sheet 3 as illustrated in FIG. 3.Preferably, in order to facilitate this operation and to minimize thepossibility of pushing the tip 17 through both sheets a porous pad 18 ofloosely woven fibers, inert to the processing fluid, is provided betweenthe sheets adjacent the seal 4. Pad 1S serves to hold the sheets 2 and 3spaced slightly apart in this injection area and therefore affords alocation easily recognizable by the user to indicate to him where thetip of the syringe should be inserted. Preferably during manufacture asmuch air as is practical is expelled from between sheets 2 and 3 sothat, prior to use, they will, as shown in FIG. 2, lie in intimateface-to-face contact with one another throughout their entire areaexcept, of course, in those areas carrying pads 14 and 18.

Inusingpthe film sandwich of FIG. l the photosensitive image area 12 isfirst exposed in a suitable camera or the like so as to produce a latentimage therein. Thereafter, either in a darkroom or a dark chamber suchas the interior of the camera, a predetermined quantity of free-flowingprocessing fluid is injected into the interior of the sandwich.` Forexample, processing may be performed in a darkroom while the sandwich issupported on a suitable supporting member 20, the end portion 21 ofwhich is preferably formed so as to support the injection area adjacentpad 18 raised slightly above the level of the image portion 9. As shownin FIG. 3 the tip 17 of syringe 16 is pushed through the sheet 3 andinto the pad 18 `and the syringefis then actuated to force its liquidprocessing composition through the pad and between `the image areas 12and 13.

In accordance with my invention the image areas 12 and 13 must be heldspaced apart from one another throughout their extent for at least apredetermined soaking period and, in order to accomplish this result,when the syringe has been emptied, it is pulled out from the sandwichand pressure is applied to the outside of the envelope so as to build upan internal pressure within the fluid 15 throughout the interior of theima-ge portion of the envelope. This may be conveniently performed withthe aid of a suitable squeegee roller 22 which, as illustrated` in FIG.4 is rolled partly across the sandwich, starting at the left-hand end,and moved to a point slightly beyond the pad 18, thereby sealin-g offthe injection opening 19 from the image porti-on and at the same timebuil-ding up a slight internal pressure within the fluid 15 so as tohold the opposin-g walls of the envelope spaced from one another, Thispressure is maintained for the desired soaking period, and then thesqueegee roller 22 is again moved t-o the right so as to produce arelatively large increase in pressure in that fluid which has not beenabsorbed yby the sheets, sufficient to cause rupture of the rupturableseal 8. During this soak period, fluid 15 .is absorbed by both negativeimage area 12 and positive transfer receiving area 13. The processing,which involves two major steps, begins and is carried out in accordancewith any one of many well known diffusion transfer process techniques.An example of a silver salt diffusion transfer process which can be usedis disclosed in U.S. Patent No. 2,352,014 to Rott. In such a process, asdescribed in Example 5 thereof, for instance, development of the exposedsilver halide takes place 4during a soaking period when the processfluid is present, as between the two sheets of the present invention.Continued movement of squeegee roller 22 across the surface of sheet 3will then press the latter into intimate face-to-face contact with sheet2 throughout the entire image area and forces all excess processingfluid into the absorbent pad 14 of trap 10. FIG. 5 illustrates theoperation as the squeegee roller approaches the right-hand end of theimage area, most of the excess fluid havin" already been forced into thepad 14 and the portion of the sheets behind the roller laminatedtogether in face-to-face relationship. As in the Rott patent, supra, theunexposed silver halide or other image forming material is dissolved andtransferred from the negative image area 12 and the positive transferimage f receiving area 13. At the completion of the required imagetransfer period, the image portions of sheets 2 and 3 will be separatedfrom one another so that the finished positive print now present on area13 of sheet 3 may be obtained. This may kbe done, for example, bycutting around the image area of the sandwich as indicated at 23 and 24in FIG. 1 and then peeling the sheets apart. Edge seals 6 and 7 may beeither cut away or, preferably, will be of such nature that they may bereadily stripped apart to facilitate such print separation.

Since the sheets 2 and 3 will ordinarily be quite flexible they willtend to bulge outwardly from one another quite readily even under therelatively low pressure applied to the fluid therein during the soakingperiod. Unless steps are taken to limit such bulging, there willtherefore be required a rather considerable amount of processing fluidin excess of that needed to perform the actual photographic processingto ensure that the interior of the envelope is sufficiently filled tohold the image areas completely spaced throughout the soaking period.The amount of fluid required can be considerably reduced if sheets 2 and3 are restrained against appreciable movement away from one another.FIGS. 6 and 7 illustrate the practice of my invention utilizing abacking member 25 for this purpose. This backing member 25 is shown asbeing provided with a pair of lateral supporting ribs 26 and 27 whichare adapted to rest on the edge portions of the sandwich as illustratedin FIG. 7 to hold the back` ing surface 28 thereof at the desiredspacing above support 20. As illustrated in FIG. 6 when roller 22 isadvanced so as to build up and maintain the desired slight pressure inthe fluid 15 during the soaking period, sheet 3 will be held by backingsurface 28 at the desired spacing from sheet 2. Backing member 25 may beeither` positively held down or, as illustrated, may be made ofsufficient weight that it will remain in position under the slightpressure used during the soaking period. At the end of the soakinginterval, member 25 will be lifted out of the way and the process willcontinue as described above, roller 22 being rolled across the sandwichto rupture the seal 8, press the image areas together, and force theexcess fluid into the absorbent pad 14.

FIG. `8 illustrates a somewhat modified form of sandwich constructionwhich incorporates the processingk fluid in compartment or chamber-31forming part of the sandwich itself. This pod or chamber 31 ispreferably at the opposite end of the sandwich from the fluid trapping`chamber 32. Like the trapping chamber it is provided with apressure-rupturable seal 33 isolating the processing fluid contents 34from the central portion 37 bearing the image areas 35 and 36. Seal 33is adapted to rupture when a predetermined pressure is built up in thefluid 34, so that the fluid may be injected between the image areas 35and 36 from the container 31. As before, the edges of the sandwich aresealed together as diagrammatically indicated at 38, 3g, 40 and 41,these edge seals being appreciably stronger than the rupturable seal 33,as well as the rupturable seal 42 separating trap 32 from the imageportion 37 of the sandwich.

This sandwich construction also illustrates another slight modiiicationin that the upper and lower sheets of the sandwich are each built upfrom several sheet sections secured together in end-to-end relationship.This permits the use, in each portion of the sandwich, of materialswhich are best adapted for the particular function of that portion. Thusthe composite upper sheet is formed by a left-hand end portion 43 whichforms the upper wall of the fiuid containing chamber 31 and which issecured as at 44 to the left-hand end of a sheet 45 oftransfer-image-receptive material. The latter is in turn secured at itsright-hand end as at 46 to another strip of sheet material 47 whichserves as the upper wall of the Huid trapping section 32. Similarly thecomposite bottom sheet is formed of a left-hand section 48 forming thebottom of the Huid container 31 and secured as at 49 to a transparentsheet of photosensitive material 5i). The opposite end of sheet 5G is inturn secured at 51 to a piece of sheet material 52 forming the bottomwall of the fluid trapping portion 32.

FIG. l() illustrates one way of accomplishing my improved process usinga sandwich construction of the type shown in FIGS. 8 and 9. Afterexposure, the sandwich is suitably supported in a darkroom or in a darkchamber such as the interior of a camera, and pressure is built upwithin the iiuid 34 in container 31 suicient to rupture seal 33 and toinject the uid between the photosensitive and transfer image areas 35and 36 of sheets 50 and 45 and to maintain the desired low positivepressure therebetween for the duration of the soaking period.Preferably, and as shown in FIG. 10 this operation is performed whilesheet 45 is backed up by means of a backing member 25 so as to limit thetendency of the sheets 59 and 45 to bulge outwardly. The desiredpressures may conveniently be built up and maintained -by rolling asqueegee roller 22 from the left end of the sandwich across thecontainer portion 31 to a position as shown in FIG. 10.

Sheets 45 and Sil are held apart from one another by the pressure withinthe luid until the end of the soaking period, at which time member 25 ismoved out of the way and squeegee roller 22 is once again moved towardthe right across the sandwich, to cause rupture of seal 42 and to forcethe remaining excess fluid into the trap 32. As before this will alsobring the transfer-receptive image area 36 of receiving sheet 45 intointimate faceto-face contact with the photosensitive image area 35 ofsheet 5t) so as to permit image transfer to obtain.

In each of the preceding cases the sandwich construction has included apressure rupturable seal between the image portion and the trappingportion of the sandwich. However such a seal is not essential to thepractice of my improved process so long as some means is provided toisolate the trapping portion from the image portion during the actualsoaking period. FIGS. 11 and 12 show sandwiches which may otherwise besimilar to those described above but in which the rupturable seal 8 or42 is lacking. Instead, prior to injection of the iluid into the imageportion of the sandwich, the upper and lower sheets are firmly pressedtogether into fluid-tight relationship along a line extending across thesandwich near the trapping section and held in this condition throughoutthe soaking period. This can be conveniently performed by means of amember 53 held tliereagainst by force exerted in the direction indicatedby the arrows. This alternative arrangement can obviously be used eitherwith or without the use of the backing member 25, FIG. 11 illustratingthe latter `and FIG. 12 the former. Moreover it is obviously possible tocombine the functions of the pressure member 53 and the backing member25. An apparatus using this type of construction, and which isespecially adapted for practicing my im proved process, is illustratedin FIG. 13.

This FIG. 13 apparatus includes a base or support 54 which movablycarries a backing member 55 as by means of pairs of swingable links 56and 57. Backing member 55 includes at its right-hand end a downwardlyextending lip or pressure member 58 which, when the member 55 is swungdown into operative position against a sandwich S9, as shown in FIG. 13,presses the upper sheet 66 thereof firmly against the lower sheet 61 toprovide the desired seal. As long as the parts are in this relationship,trapping portion 62 of the sandwich is eifectively isolated from theremainder thereof. In using this apparatus to practice my invention, thesandwich, after it has been exposed, is positioned on support 54 asshown in FIG. 13 and the member 55 is swung down into operativeposition. Cons veniently a resilient catch 63 cooperating with a pin 64may be used to maintain the desired pressure on the seal ing lip 58.Fluid is then injected from the container portion 65 into the imageportion of the sandwich as by means of a squeegee roller 22 aspreviously described, sucient force being maintained on roller 22 sothat the desired small positive pressure will be maintained in ther'luid throughout the soaking period. At the end of this period member25 will be swung out of the way and roller 22 rolled across the imageportion to laminate the image areas together and to force the excessfluid into trapping portion 62 as previously described.

FIG. 14 diagrammatically illustrates a camera 76 of a type adapted foruse in practicing my improved processing operation within the cameraitself. Camera 70 is adapted to hold a supply roll '71 of a continuousstrip of composite image transfer film product 72 which includes aplurality of sandwich portions 73, similar to those previouslydescribed, connected in end-to-end relationship with one another byconnecting strip portions 74. Each sandwich preferably includes a fluidcontainer 75 at its leading end, and a trapping portion 76 at itstrailing end. The strip 72, including the sandwiches 73 is arranged tobe threaded from the supply roll 71 past an exposure station 77, thencethrough a processing chamber 7S and out a suitable exit aperture 79.Suitably mounted within the processing chamber 7S is a squcegee rollerSil which is adapted to be traversed downwardly and rearwardly over theforward wall S1 of the chamber 78 by pulling an actuating knob S2,coupled to the roller, in the direction of the arrow 83. Also movablymounted within chamber 78, as by suitable swinging links 84 and 85, is abacking member 86 which includes a transversely arranged lip or sealingmember S7 adjacent its lower end. As shown in FIG. 14, lip S7 is adaptedto bear against a sandwich located in the processing chamber 78 so as toseal the trap 76 thereof from the image portion 8S during the soakingperiod. Backing member 86 may be swung from its operative position shownin FIG. 14 to a relatively raised position by swinging a lever 89,connected to link 84, in the direction of the arrow 9G. Preferably asuitable toggle spring 91 is provided to hold backing member 86 ineither its operative or inoperative position.

In using a transfer image product of the type under consideration, wherethe exposure is made through the sensitized sheet itself, the positivetransfer image which would be obtained would normally be reversed, leftto right, unless steps were taken to prevent this. In the cameraillustrated this is done by providing a mirror 92 for reilecting thelight passing through lens 93 onto the film product at the exposurestation 77 and thereby effectively reversing the negative image. Withsuch an arrangement the finished print will show the proper orientation.The camera also preferably includes a suitable cutter 94 adjacent theexit slot 79 for separating processed envelopes from the remainder ofthe strip.

In use, the end of the strip 74 protruding through opening 79 is graspedby the operator and pulled to an extent suicient to bring the imageportion of the first envelope into position `for exposure at theexposure station 77. After exposure, the strip is` again pulledsufficiently to move the exposed sandwich into processing position inchamber 78. This is the relationship actually illustrated in FG. 14.Lever 89 is then swung in its counterclockwise direction to move backingmember 86 into the operative positive position shown, with its rib S7sealing the trap 76 from the image portion 88 of the sandwich. Knob 82is then pulled so as to move roller 80 a sutiicient distance to rupturethe container 75 and force its contents into the image portion o-f thesandwich and to maintain the desired slight positive pressure therein.At the end of the predetermined soaking7 period lever 89 is swungclockwise to lift backing member 86 out of the way and knob 82 is pulledto the limit of its movement, during which roller 80 will move asuicient distance to squeegee the image portions of the sheets of thesandwich rmly together and to force the excess processing fluid into thetrap 76. Roller 80 may then be returned to its inoperative position byreturning knob 82 to the position shown. At the end of the imagetransfer period the end of the strip is once again pulled to bring thenow-processed sandwich out of the exist slot 79 so that it may be cutfrom the strip 72 and separation of the negative and positive imageareas may be performed. This operation also moves `the stripsufticiently to bring the next sandwich portion into exposure position.

My improved process is obviously substantially independent of thespecific photographic image-transfer compositions yand materialsutilized except insofar as they alfect the amount of processing fluidrequired for proper processing, and no detailed description of thespecific materials is believed necessary in this application. Sufce itto say that almost any known image transfer materials could be utilized.For example, the sensitized sheet, the receiver sheet and the processingliuid itself may conveniently ybe of the type fully disclosed `in theCanadian patent to Whitmore etal., 602,607, dated Aug. 2, 1960.Photographic materials of the type used in the presently commerciallyavailable ,image transfer lilms could likewise be used, except, ofcourse, that the processing fluid itself should be substantiallyfree-owing rather than viscous as normally used with such commercialproducts. Both the sensitized and receiver sheets should preferablyinclude at least one layer which is imperivous to the.

processing lluid and the inner walls of the fluid container itselfshould, of course, be of a material which will not react with theprocessing fluid. Suitable materials and techniques forobtaining theseresults are well known in the art and require no further descriptionhere.

It should be pointed out that, in order to bestillustrate by invention,the relative thickness of the materials used has been greatlyexaggerated in the drawing, particularly as regards the thickness of thelayer of processing iiuid. In practice therefore the fluid containerandthe trapping mem-ber will protrude above the general plane of thesandwich to a much lesser extent than as illustrated. It has been found,for example, that with materials of the type described in theabovementioned Canadian patent, the iilm and receiver sheets togetherwill absorb, during the soaking period only about cc. of processingfluid per square foot of area (of one sheet) over which the fluid isapplied. This corresponds to a layer of fluid which, prior to soaking,would be only about .O02 inch in thickness. However since it is desiredthat the opposing image areas be held completely out of contact with oneanother throughout the entire soaking period, the amount of processinguid provided should be such that the layer of fluid over the image areaat the beginning of the soaking period will preferably -be 50 percent ormore thicker than that required for the actual photographic` processing.This insures that soaking will be uniform over the entire image area.The excess tiuid is, of course, squeegeed into the trapping portion ofthe sandwich and absorbed therein at the end of the soaking period, aspreviously described.

It is, of course, to be understood that the above example is butillustrative, and is in no sense intended to be limiting, since theactual amount of processing iluid required will, as mentioned before,depend to a considerable extent upon the particular photographiccompositions and materials used in the sandwich. However for anyparticular materials the amount of fluid required for proper soaking maybe readily determined and the amount provided should exceed such valuesuiiiciently to keep the image `areas spaced `from one anotherthroughout the soaking period.

While in the sandwich Constructions illustrated, the edges and ends havebeen described as being positively bonded or sealed together prior touse, any or all of these seals could be eliminated and suitable pressuremembers could be provided for temporarily holding the correspondingareas of the sheets together during processing to form the desiredfluid-tight envelope.

Other pressure means than a squeegee roller could also obviously be usedto force the iiuid into the imagearea and later into the trappingportion and the sandwich,

rather than the pressure roller or other pressure means,`

could be moved to produce the desired uid distribution and pressure.

Similarly many other changes could be made in the product and apparatusused in practicing my improved process without departing from the spiritand scope of my invention as defined by the appended claims.

I claim:

1. The method of processing a photographic product of the typecomprising a rst strip of sheet material having a photosenstive imagearea on one face thereof and a second strip of sheet material overlyingsaid one face and having a transfer-image-receptive image areacorresponding to and substantially coextensive with said photosensitivearea and lying in substantial face-to-face contact therewith, said imageareas being adapted for conjoint photographic processing in the presenceof an appropriate processing liquid, said method comprising:

exposing said photosensitive image area to form a latent image therein;

injecting a predetermined quantity of a free-flowing processing liquidbetween said image areas while coniining said liquid betweenpredetermined portions of said strips including at least those portionsbearing said image areas;

subjecting said confined liquid to, and maintaining it for apredetermined period under, a positive pressure sufiicient to separateand to positively hold said image areas spaced apart from one anotherthroughout their extent for the duration of said period;

at the end of said period,

releasing said confined liquid; and

pressing said image-area-bearing portions of said strips together, withsaid image areas once again in intimate face-to-face contact with oneanother.

2. The method as set forth in claim 1 wherein the said predeterminedportions of said strips between which said liquid is confined arebounded at least in part by a seal, rupturable upon the pressure withinsaid confined liquid reaching a predetermined value,

the pressure in said liquid throughout said period being maintained at avalue below said predetermined rupturing value,

and wherein release of said `liquid at the end of said period isproduced by increasing the pressure therein to said rupturing value torupture said seal.

3. A photographic product comprising a pair of sheets of uid imperviousmaterial,

at least one of said sheets carrying on one face thereof a iiuidabsorptive image area,

said other of said sheets being superimposed on said one sheet so thatan area thereof overlies said image area in intimate face-to-facecontact therewith throughout said areas,

portions of said sheets surrounding said areas being sealed together toform a substantially fluid-tight envelope section enclosing said imagearea,

at least certain portions of said envelope section being flexible topermit complete separation of said image area and the overlying area ofsaid second sheet upon injection of a predetermined quantity f freeowingprocessing liquid therebetween,

one of said sealed portions being relatively weaker than the otherswhereby it will rupture upon generation of a predetermined pressure insuch iiuid within said envelope and release the excess processing fluidfrom said envelope section.

4. A photographic product as in claim 3 further comprising a trap forexcess fluid separated from the interior of said envelope section bysaid rupturable seal.

5. A photographic product as in claim 3 wherein further portions of saidsheets are sealed together to form a second duid-tight envelope sectionalongside said first envelope section and separated therefrom by saidrupturable seal thereby forming a trap for excess uid released from saidrst envelope section.

6. A composite photographic product for image transfer use comprising arst sheet, at least a portion of one face of which constitutes aphotosensitive image area;

a second sheet overlying said one face of said rst sheet, that portionof said second sheet directly opposite said photosensitive image areaconstituting a second image area receptive to a transfer image whenprocessed in conjunction with said photosensitive image area and aprocessing fluid;

opposed portions of Said sheets lying outside of said image areas beingsecured together to form a continuous fluid-tight seal completelysurrounding said image areas,

at least a portion of one of said sheets being flexible whereby saidimage areas are free to separate from one another throughout theirentire extent without rupture of said seal upon injection of processingiluid therebetween,

a selected portion of said seal being more readily rupturable than theremainder of said seal whereby said portion of said seal Will rupturewhen fluid pressure between said areas exceeds a predetermined value.

7. The method of photographic processing involving the use of anenvelope sealed completely about its peripheral edges and having opposedinner Wall surfaces of fluid absorptive image-receptive material adaptedfor conjoint processing and one of which surfaces carries a latent imagetherein, comprising the steps of:

injecting between said image receptive surfaces a freeflowing processingliquid in such quantity and under such pressure as to hold saidimage-receptive wall surfaces spaced from one another for a rstpredetermined period,

at the expiration of said period,

removing the remaining unabsorbed liquid from between said surfaces,

pressing said surfaces together in face-to-face relationship, andmaintaining them thus for a second predetermined period,

and thereafter separating said surfaces.

8. The method of photographic processing involving the use of anenvelope having opposed inner wall surfaces at least one of which is offluid absorpti've, image-receptive material adapted for processing inconjunction with an appropriate free-flowing processing liquidcomprising:

lling said envelope with such processing liquid suffii0 cient tomaintain said surfaces spaced from one another for at least apredetermined period,

holding said liquid within said envelope for such period and under suchconditions that said liquid will maintain said surfaces thus spaced fromone another throughout said period,

at the end of said period;

removing the unabsorbed liquid from between said surfaces,

and pressing said surfaces into substantial face-to-face contact withone another.

9. The method of processing a photographic product of the typecomprising a first strip of sheet material having a photosensitive imagearea on one face thereof and a second sheet overlying said one face, andhaving an area thereof corresponding to and substantially coextensivewith said image area lying in substantial face-to-face contacttherewith; said method comprising:

exposing said image area to form a latent image therein;

injecting a suflicient quantity of a substantially freeiiowingprocessing liquid between at least those portions of said strip bearingsaid areas to cause said areas to separate completely from one anotherthroughout their extent;

maintaining such fluid bet-Ween said areas under a positive pressure fora predetermined processing period so that said fluid will hold saidareas completely spaced from one another throughout said period;

at the end of said period;

relieving the pressure on said liquid;

and pressing those portions of said sheet bearing said areas together sothat said areas are again in intimate face-to-face contact with oneanother.

10. The method of processing a photographic imagetransfer product of thetype comprising a pair of strips of sheet material each having an imagereceiving area thereon, said strips being arranged so that said imageareas normally lie in substantial face-to-face contact with one anotherthroughout the extent of said areas, one of said areas beingphotosensitive and the other being transfer-image-receptive, said methodcomprising:

exposing said photosensitive image area to produce a latent imagetherein;

injecting between at least the image area-bearing portions of saidstrips a sufficient quantity of a processing liquid capable ofinitiating development of said photosensitive image area and imagetransfer therefrom to said transfer-image-receptive area to cause saidareas to separate completely from one another throughout their extent;

maintaining such liquid between said areas under a positive pressure fora predetermined period so that said liquid will hold said areascompletely spaced from one another throughout said period;

at the end of said period,

relieving the pressure on said liquid;

and pressing the image-area-bearing portions of said strips together sothat said image areas are again in intimate face-to-face contact withone another to permit image transfer therebetween.

1l. The method as set forth in claim 10 comprising the additional stepsof:

maintaining said image areas in said last mentioned relationship for asecond predetermined period to bring about the formation of a transferimage in said transfer-image-receptive area;

and, at the expiration of said second period, separating at least thatportion of the strip bearing said transfer image from said other strip.

12. The method of processing a photographic image transfer lproductincluding a photosensitive layer and a transfer-image-receiving layercomprising:

Iforming a fluid-tight chamber with the photosensitive layer carried onat least a portion of the inner face of one wall of said chamber, andthe receiving layer carried on the inner face of that wall portiondirectly opposite said sensitive layer, said chamber including exiblewall portions permitting relative movement between said layers;

exposing said photosensitive layer to produce a latent image therein;

injecting into said chamber a substantially free-flowing processingliquid capable of initiating processing of said exposed photosensitivelayer and image transfer to said receiving layer;

maintaining said liquid under sufficient pressure throughout saidchamber to hold said opposed layers spaced materially apart from oneanother by said liquid for a predetermined period thereby substantiallypreventing image transfer therebetween during such period;

and at the expiration of said period,

relieving the pressure on said liquid;

and pressing said opposing layers together into intimate face-to-facecontact to force excess liquid from therebetween and to cause imagetransfer to said receiving layer.

13. The method of processing a photographic image transfer productincluding a photosensitive layer and a transfer-image-receiving layerproviding negative and positive image areas respectively comprising:

forming a fluid-tight chamber, with the negative image area of saidphotosensitiveilayer carried on at least a portion of the inner face ofone Wall of said chamber, and the positive image area of said receivinglayer carried on the inner face of that wall portion directly oppositesaid negative image area, said chamber including flexible wall portionspermitting relative movement between said image areas, and at least oneof said opposed wall portions being substantially transparent to lightactinic to said photosensitive layer;

exposing said negative image area of` said photosensitive layer throughsaid transparent wall portion to form a latent negative image in saidimage area;

releasing into saidchamber a substantially free-flowing processingliquid capable of initiating processing of said photosensitive layer andimage transferto said receiving layer;

maintaining said liquid under sufcient pressure throughout said chamberfor a predetermined period to hold said negative and positive imageareas spaced apart from one another by said liquid so as to preventimage transfer therebetween during such period;

and, at the expiration of said period, relieving the pressure on saidliquid;

and pressing said opposed Walls together to bring said image areas intointimate face-to-face contact to force excess liquid from therebetweenand to cause image transfer to said positive image area.

14. The method of processing a photographic image area comprising:

forming a fluid-tight chamber, at least a portion of the inner face ofone wall of which comprises said area, said chamber including ilexiblewall portions` permitting relative movement between said area and theopposing wall of said chamber;

injecting into said chamber a substantially free-flowing processingliquid capable of initiating the photographic processing of said imagearea;

maintaining said liquid under throughout said chamber to hold said areaand ,said opposing wall spaced apart from one another by said liquid fora predetermined period;

at the expiration of said period,

relieving lthe pressure on said liquid;

and pressing said area and said opposing wall together into intimateface-to-face Contact to force excess liquid from therebetween.

15. The method of processing an exposed photographic image area,comprising:

forming a fluid-tight envelope with said image area on the inner surfaceof one wall thereof;

injecting between said area and the opposing wall of said envelope aprocessing iiuid capable of photographically processing said area;

producing a positive pressure throughout said uid by external pressureapplied to portions of the envelope walls lying outside of the limits ofsaid image area and in contact with said fluid, suicient to hold saidopposing wall spaced from said image area throughout the entire extentof the latter;

maintaining said pressure for a predetermined processing period;

at the end of said period,

releasing said fluid from between said area and opposing wall;

and pressing said ,area and opposing Wall into intimate face-to-facecontact throughout the extent of said area.

16. The method as in claim 15 wherein said positive pressure is producedby causing relative movement between said envelope and coacting externalpressure applying means whereby said envelope wall portions areprogressively forced into contact with one another beginning at alocation spaced materially from said image area and moving relativelytoward said image area until said pressure attains the desired value.

17. The method of claim 16 wherein said envelope includes a pressurerupturable seal securing the walls of said envelope together adjacentone edge of said image area;

said fluid being released and said image area and :its opposing wallbeing pressed together by resuming said relative movement of saidenvelope and said pressure means at the end of said period, therebyincreasing the pressure within the fluid to a value sufficient torupture said seal and to thereafter progressively force unabsorbed fiuidfrom between said image area and its opposing wall and through saidruptured seal.

References Cited UNITED STATES PATENTS 2,455,111 11/1948 Carbone et al.96-29 X f 2,544,268 3/1951 Land 96-29 X 2,627,460 2/1953 Land 96-76 X2,966,103 12/1960 Erickson 96-29 X 2,982,650 5/1961 Land 96-76 NORMAN G.TORCHIN, Primary Examiner.

R. MARTIN, Assistant Examiner.

suilicient pressure

1. THE METHOD OF PROCESSING A PHOTOGRAPHIC PRODUCT OF THE TYPECOMPRISING A FIRST STRIP OF SHEET MATERIAL HAVING A PHOTOSENSITIVE IMAGEAREA ON ONE FACE THEREOF AND A SECOND STRIP OF SHEET MATERIAL OVERLYINGSAID ONE FACE AND HAVING A TRANSFER-IMAGE-RECEPTIVE IMAGE AREACORRESPONDING TO AND SUBSTANTIALLY COEXTENSIVE WITH SAID PHOTOSENSITIVEAREA AND LYING IN SUBSTANTIAL FACE-TO-FACE CONTACT THEREWITH, SAID IMAGEAREAS BEING ADAPTED FOR CONJOINT PHOTOGRAPHIC PROCESSING IN THE PRESENCEOF AN APPROPRIATE PROCESSING LIQUID, SAID METHOD COMPRISING: EXPOSINGSAID PHOTOSENSITIVE IMAGE AREA TO FORM A LATENT IMAGE THEREIN; INJECTINGA PREDETERMINED QUANTITY OF A FREE-FLOWING PROCESSING LIQUID BETWEENSAID IMAGE AREAS WHILE CONFINING SAID LIQUID BETWEEN PREDETERMINEDPORTIONS OF SAID STRIPS INCLUDING AT LEAST THOSE PORTIONS BEARING SAIDIMAGE AREAS; SUBJECTING SAID CONFINED LIQUID TO, AND MAINTAINING IT FORA PREDETERMINED PERIOD UNDER, A POSITIVE PRESSURE SUFFICIENT TO SEPARATEAND TO POSITIVELY HOLD SAID IMAGE AREAS SPACED APART FROM ONE ANOTHERTHROUGHOUT THEIR EXENT FOR THE DURATION OF SAID PERIOD; AT THE END OFSAID PERIOD, RELEASING SAID CONFINED LIQUID; AND PRESSING SAIDIMAGE-AREA-BEARING PORTIONS OF SAID STRIPS TOGETHER, WITH SAID IMAGEAREAS ONCE AGAIN IN INTIMATE FACE-TO-FACE CONTACT WITH ONE ANOTHER.